1. Field of the Invention
The invention relates to an operating pedal device for a vehicle, such as a brake pedal device, and especially relates to a connecting structure of a pivotally connecting portion that transmits an operation force through a connecting pin.
2. Description of the Related Art
An operating pedal device for a vehicle including an operating pedal, a reaction force member, and a pivotally connecting portion has been widely used in a brake pedal device for a service brake or a parking brake, etc., for example. The operating pedal is mounted on a pedal support which is fixed to a vehicle pivotablly about the supporting axis and is depressed by a driver. The reaction force member is a member to which an operation force of the operating pedal is transmitted and on which a reaction force corresponding to the operation force is acted. The pivotally connecting portion is mounted between the reaction force member and the operating pedal or between a transmitting member that transmits the operation force to the reaction force member and the operating pedal. The pivotally connecting portion connects them relatively pivotablly about a connecting pin that is parallel to the supporting axis, and transmits the operation force through the connecting pin.
One example thereof is an apparatus disclosed in Patent Document 1 (JP-A-2007-122610). The operating pedal has a hollow structure, and the pivotally connecting portion is provided with connecting holes, which is in a pair of side plate parts located on the both sides in the vehicle width direction, formed in a straight line substantially parallel to the supporting axis. The connecting pin is inserted through both of the connecting holes of the side plate parts of the both sides, and the reaction force member is connected thereto through a clevis or the like.
Further, in Patent Document 2 (JP-A-11-115699), an intermediate lever which is mounted on the vehicular front side of the operating pedal pivotablly about an intermediate axis that is parallel to the supporting axis is disclosed. The intermediate lever is connected to the operating pedal through a connecting link, and is mechanically pivoted about the intermediate axis in accordance with the depressing operation of the operating pedal, thereby the operation force is transmitted to the reaction force member. In such a link-style operating pedal device, the connection portion between the connecting link and the operating pedal corresponds to the pivotally connecting portion, and the connecting link corresponds to the transmitting member.
However, according to the structure in which a connecting pin is inserted directly into connecting holes formed in a pair of side plate parts of an operating pedal having a hollow structure, an operation force (reaction force) intensively acts on edges of the connecting holes. This may result in buckling or deformation, and accordingly, there arises a necessity to increase the plate thickness of the operating pedal. In Patent Document 1, a collar is fixed to a connecting hole on one side plate part, whereby the workability upon the insertion of a connecting pin is improved and the strength is increased. However, in the side plate part on another side, problems of buckling and deformation still remain.
Against these problems, measures as shown in FIGS. 6A and 6B can be taken. FIGS. 6A and 6B are sectional views showing a pivotally connecting portion 112 where the operating pedal 100 is connected to a push rod 110 as a reaction force member. The operating pedal 100 is formed of a pair of half-divided bodies 102 and 104, as in the above Patent Document 1. The side edges of the pair of half-divided bodies 102 and 104, i.e., edges in the back and front or the top and bottom directions of the vehicle, are integrally weld-joined, and are relatively pivotablly connected to the push rod 110 through a clevis pin 106 and a clevis 108.
FIG. 6A shows an example in which the above-mentioned half-divided bodies 102 and 104 are provided with, burring holes 114 and 116 projecting inwardly as connecting holes, respectively. In this case, a reaction force acts intensively on the burring holes 114 and 116, and therefore, the problems of abrasion, buckling, and the like cannot be sufficiently solved. FIG. 6B shows an example in which a cylindrical collar 120 is mounted through both of the burring holes 114 and 116. In this case, the workability upon the insertion of the clevis pin 106 is improved, and abrasion is also alleviated. However, a reaction force acts intensively about the burring holes 114 and 116, and thus the possibility of buckling still remains.
Meanwhile, when a hollow-structured operating pedal is used in a link-style operating pedal device as disclosed in the above Patent Document 2, because of the existence of an intermediate lever on the vehicle front side, the size and shape of the operating pedal are limited. This makes it even more difficult to secure the rigidity and strength of a pivotally connecting portion. That is, for example, as shown in FIG. 1A, a space A that allows depressing operation of the operating pedal 14 has to be secured between an intermediate shaft 16 in front of the operating pedal 14 and the operating pedal 14, and also a space B for footwork has to be secured at the back of the operating pedal 14, i.e., on the drivers side. As a result, the width dimension of the operating pedal 14 in the fore and aft direction (horizontal direction in FIG. 1A) is limited.
The invention was accomplished against the above background. An object thereof is to increase the rigidity of a pivotally connecting portion to which a reaction force member or a transmitting member is connected with a connecting pin to thereby prevent buckling and deformation, while keeping the plate thickness of a hollow-structured operating pedal small to minimize the weight and size thereof.